Analog Discovery by Digilent

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I am using mine a lot as a network analyzer to check open loop as well as closed loop response, magnitude and phase. It is a great tool to check phase- and gain margin for stability. It shows for instance that 10dB hump at 1MHz that causes all the hf noise ;-)

Jan

Hi Jan,

Do you mind giving us some details of how you measure loop gain with the analog discovery for amplifier stability investigation purposes?

I found this procedure: https://wiki.analog.com/university/courses/electronics/electronics-lab-loop-gain

Do you do something similar (i.e inject a signal via a transformer into the feedback loop)?

As you know, there are a few methods of measuring loop gain (some more accurate than others). I'm very interested to know which one you have found is the best.

Thanks,
Ian
 
I have the FrontBox for the AD but haven't played with it much yet.

BK
 

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Hi Jan,

Do you mind giving us some details of how you measure loop gain with the analog discovery for amplifier stability investigation purposes?

I found this procedure: https://wiki.analog.com/university/courses/electronics/electronics-lab-loop-gain

Do you do something similar (i.e inject a signal via a transformer into the feedback loop)?

As you know, there are a few methods of measuring loop gain (some more accurate than others). I'm very interested to know which one you have found is the best.

Thanks,
Ian

Well I must admit I haven't done anything so sophisticated (but planning to; I did buy a wideband isolation xformer from Omicron).
So far I have done measurements in closed loop but progressively lowering the feedback (higher CL gain). I don't get all the way to OL but you get lots of info already.

Jan
 
That is a very nice box! I wonder what it costs; is it also from Digilent?

Jan

You can click the link to go to the product page. From Softone in Japan, not Digilent. Seems to be discontinued now. I paid $80 as a kit. Quality is very high! The steel case is very nicely done and superbly finished - I wonder if Softone could still make PCBs only available?

BK
 

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Hi Frex,
Analog Discovery as Impedance Analyzer with the cool software of TheStuffMade.
It's only connectors and one resistor..Difficult to do simpler than that !
---snip---
Anyway, it can be used as is and work very great
Got a Discovery2.
Waveforms network analyzer works.
Audio Analyzer Suite 1.0.0.71 connects to Discovery2.
Impedance Analyzer 1.0.0.36 shows devices properties for a short moment and switches shortly after that to "Device not available". :(
Unfortunately, this great designer doesn't answer message on his own site
=> Advice is much appreciated.
Thanks
Ulli
 
I just can say something other, his Impedance analyzer software seem to be regularly updated,
i use it from at least 6 months and few weeks ago a newer version has added some notable improvements
like graph memory (to compare measurements graphically) and full data export in csv form.
These improvement are really very useful !

Frex
 
I just can say something other, his Impedance analyzer software seem to be regularly updated,
i use it from at least 6 months and few weeks ago a newer version has added some notable improvements
like graph memory (to compare measurements graphically) and full data export in csv form.
These improvement are really very useful !

Frex

That's great to hear Frex, it would be perfect for some audio LC circuits I'm working on. I'm hoping that he gets around to releasing the hardware to a wider audience as it seemed he once intended to.
 
one word of caution for those using the square wave generator (at least on the latest version of the hardware/software)

When you switch off the generator in the software, it seems to leave the output in the high (or low) state... so be careful in case you're driving a DC coupled power amp !
 
I just can say something other, his Impedance analyzer software seem to be regularly updated,
i use it from at least 6 months and few weeks ago a newer version has added some notable improvements
like graph memory (to compare measurements graphically) and full data export in csv form.
These improvement are really very useful !

Frex

Hi Frex
I tried installing the latest version available from the Stuffmade website, but can't get it working in Win7. There is like an activation error, see screenshot attached
Can you please share your latest working binary? There are no previous versions in the website unfortunately.
thank you
Ale
 

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